thanks sazzy, for writing the response that i didn't have time to because i was at work :D
one more point to add/expand on, alongside what you mentioned about pc games and hardware is that while it's possible to make things run at the highest res with high levels of anti aliasing and detail etc, it's really not in developer's interests to do that - the options are always there, but they wouldn't make any money at all, as the rich graphics whores who demand their games to run this way are not actually that common any more - despite what web forums would have you believe :D
(an example of this existing outside of the pc gaming world would be with gt5 on the ps3 - the 200 odd premium car models - the very highly details ones - were originally rendered at a much, much higher resolution than 1080p. this allows them to simply drop these 200 models into the next game on the next platform sony releases. they have the ability to create the models now, but they can't render them in game on the current tech. this will change with the next playstation. pc gamers potentially have the possibility of taking advantage of things such as this right here and now, but for a price, and the price is high.)